Ice manufacture



it i fff'si' i f :Be t' known that I,;R1DsDALn ELLIS, a'ci-t-, ize'n' 0fthe United States, and a resident of 'Thisinyeiition relates to themanufacture of artificial ice and more; particularly "to fanda cloudybutt-greatly. detracts from its Small amounts of readily soluble saltsand' magnesium salts, particularly the car- 'known' inthe art as a limepocket.

- is -usua'1to soften'the-=Wate'r to reduce the content of calclum and"magnesium :salts to Patented July 3, 1923.

ICE Menu iNo Drawing.

To all whom it may concern Oak Park, in the county' of Cook and State ofIllinois, haverinvented certain new and useful 'Im'prouenients in IceManufacture, (if which the following is-a specification.

raw-water ice as distinguished from diS- tilled Water 1ce.

the freezing of Water containinglsalts y 1n solutlon crystals'of'ice'entirely free from dissolved materials-separate out leaving the 'saltsinthe unfrozen water. theco'ncentration of these salts in theneighbourhood of the 'ice'cry'stals increases beyond the saturat1o'npoint small crystals of salt are formed andfthese'become embedded in theice cake p'arti'cularlyin'the lower part of the cake to form a Whitecloudy butt. For a cake to be readily saleable itjm'ust-be substantial-1y clear except for av feather down the center value.

such as sodium earbonateare not in general deleterious but smallquantities of calcium bonates 'of these metals and the hydroxide (theirWide distribution precipitation ofv 'ithese f salts begins very shortlyafter the water has begun to'freeze.

. Such an accumulation ofcalcium and magnesium salts' in the butt ,ofthe ice cake is To reducethe sizeofthe lime pockets it a minimum.

" The usual' softening treatment basedon the great difierence insolubility betweenthe 'noifm'al carbonates and bicarbonates. ofcalciumand the ne arlyinsoluble character'of magnesium hydroxide-1* ,Thesolubility oft; the'l'atter is only about 0.9 parts per 100,000.

solubility of normal calcium carbonate?- take toforrn a lime pocket.lVhenthe Water cont alns excessive amounts FAcTunn s Application filedian'uary 20,-191a.; Serial No 272,212."

.RIDSDALE ELLisjoF oak rAn'izQ ILLINOIS.

' is "about "l.3 parts per: 100,000 and that f magnesium carbonateisabout 10.6parts per "100,000. The solubility of these carbonates hasbeen shown to increase proportionately to the amount offree.carbonl'dioxide present By adding 'lime the freerarbon-"dio xide may beneutralized and the'bicarbonates con- :so' that in" Waters high :in freecarbon d'idX- I ,ide' the"calcium' carbonate may run as high "as 60parts per 100,000 or higher; The/same ;is true of' magnesium carbonate;1

yertedinto normal carbonates thereby 'precipitating calcium carbonateand some mag- "nesium' c'arbonate'if the "contentiof magnesium salts ishigh; To eliminate-the unprecipitated magnesium. salts *additional' limeis'added. "Carbonate of soda 'i -7 s 0 v for" precipitating sulphates-,-vchlorides, etc.,

of calcium. 1

sium is never'what it shouldbe theoretically OWlIigutQT the phenomenonof supersaturation; a so" that the resulting; softened water usuallycontains about 3?; to 4 .apELI'tS of cal-- The pre ipiitationofcalcium'andimagne- 1ciu1n' carbonate and about 1% to? parts'go'fi magnesiumhydroxide per 100,000,

The clear portions of'ice obtained-from such softened water do notcontain-more, than 05parts per 100,000 of calciumnand magnesium saltssothat at least %"of3 h latter salts vare concentrated in the centerandm'ore particularly inthe butt of mineral salts-it is usual :to' pullthe cores ,i-:in. other words to remove bysuction the unfrozenWaterafterthe'cans'haVe -been, say,*- ,frozen and then replace/"thewater.withdrawnv by fresh water: seen a OfqilhGiCB 85,. a I

method 'isflnot, howe er, ordinarily adapted the butt during, almostthe'wivhole freezing operation. s v; In most, raw-water: ice ;plants.a1r. 1s blown throughthe water during the freezing op- I eration forthe primary purposeof; prevente:

-fo'r theelimination of -,the calciumandzmagnesium salts asthese do not,concentrateiin solution but precipitate out and freeze intoai9 ingthebubbles -Of:a.iI carbon dioxide, etc,

liberated from solution 'f-ree'zing into the ice and thereby making, thecakecloudy and opaque or as is Eknownin the art a .ftoinblarly desirablewhen such substances are used to avoid the lime pockets as there isnothing to keep the precipitated lime from; freezing into the ice evenif core pulling is resorted to. Hence when such substances as citricacidor citrates are employed without agitation it is' particularlydesirable to employ means for eliminating the lime pockets.

The principal objects of my invention are the provision of an improvedmeans of treatmg water for avoid ng .the formation of lime pockets,theprovision of an improved method of treating Water for ice manufacture,and generally to improve, simplify and cheapenthe manufacture ofartificial ice.

According to my invention I add to the water substances adapted to bringthe cal- "cium and magnesium compounds into a more soluble form. Forthis purpose I preferably employ compounds adapted to form double saltswiththe calcium and'magnesium present such as salts of ammonium and moreparticularly ammonium chloride.

The amount of ammonium chloride is not under ordinary circumstanccsinexcess of three times the amount of calcium and magnesium saltspresent. This quantity of ammonium chloride will increase thesolubilities'of these compounds much in excess of five times theirprevious value. 1

Usually I prefer to soften the water to remove as much of the calciumand magnesium as possible before adding the ammonium chloride. Where thewater is naturally comparatively soft this softening treatment may insome cases be dispensed with although usually desirable for the purposeof eliminating the carbon dioxide both free and combined as bicarbonate.

In carrying out my invention in its preferred form I soften the waterwith lime and soda in well-known manner with the addition of a smallamount of citric acid or its equivalent. The amount of citric acidrequired varies somewhat but for the Water from Lake Michigan, forexample, 6 ozs. of

-c1tr1ca0id't0 16,000 gallons of water is satisfactory. "To the softenedwater is added about QO lbs. of ammonium chloride and then the water is"ready for freezing.

I Usually the ice is frozen without core pulling but m'some cases it maybe desirableto pull the cores especially in the case of waters high insoluble mineral salts. Since theaddition of ammonium chloride increasesthe solubility of the calcium and magnesium;

salts the latter remain in solution until the greater part of the waterhas frozen instead of precipitating during practically the wholefreezing operation so that by pulling the cores substantially all ofthe. calcium. and magnesium salts can be removed.

Having thus described my invention and illustrated its use, what I claimas new and desire to secureby Letters Patent is 2- l. The process ofmaking raw Water ice which includes subjecting the Water to softeningtreatment e to eliminate calcium and magnesium salts then adding a"substance adapted to increase materially the solubility of the calciumand magnesium compounds remaining in the Water after the softeningtreatment and then freezing the Water so treated. 2. The process ofmaking raw water ice which includes adding'a substance adapted tomaterially increase the solubility :of the calcium and magnesiumcompounds and then freezlng the water so treated.

8. The process of making-raw waterice whichiincludes adding a saltadapted to increase materially the solubility of the;car-' respectivelyof i cal-,

bonate and hydroxide cium and magnesium and then freezing the water 50treated. l V

' 6. The process of making, raW water ice which includes adding a saltadaptedto form a soluble double salt with the calcium andmagnesium'salts in the water and: then freezing the water sotrea'ted;

7. The process of making raw Water ice which includes adding an ammoniumsalt to increase the solubility of the calcium and :1

'magnesium compoundsin the Water and then freezing the water so treated.

8. The process of making raw water ice which includes adding ammoniumchloride to increase the solubility of the calcium and magnesiumcompounds inthe water andthen freezing the'water so treated.

9;..The process of making raw waterice which includes subjecting thewater to softening treatment to eliminate calcium and! magnesiumcompounds then adding an ammonium salt to increase the solubility of thecalcium and magnesium compoundsremaining .in the water after thesoftening treatment and then freezing the water-so treated.

10. The process of making raw Water ice which includes adding-amaterial: adapted to inhibit the freezing of gas bubbles into the itsprevious value and then freezing the 10 water so treated. j v

12. The process of makingcravv water ice Which includes adding an,ammomium salt in sufiicient amount to increase the solubility of thecalcium and magnesium compounds 15 more than five times and thenfreezing the Water so treated.

I RIDSDALE ELLIS.

